The
endbell from SEALAB II and III outside the Naval Undersea
Museum, Keyport

Close-up of the SEALAB
endbell

SEALAB
II was designed, built, and outfitted at Hunterís Point Naval
Shipyard in San Francisco. The Navy lowered it to the sea floor off
La Jolla, California, in the fall of 1965. It was designed to
house ten men at a depth of 200 feet for 30 days. The habitat
was 50í long and 12í in diameter, and included four separate
areas: entry, laboratory, galley, and living
spaces. Entry while on the ocean floor was from below the
habitat, with divers emerging into the pressurized habitat through
an open moon pool.

Whereas
SEALAB I tested and proved the concept of saturation diving, SEALAB
II provided evidence that useful work could be done. The Navy
conducted physiological and psychological studies to determine manís
effectiveness underwater for an extended period. The divers
evaluated the structural engineering of the habitat. They
worked on a mock-up of a submarine hull and tested undersea tools;
they raised an old navy jet fighter to the surface using syntactic
foam; they set up a weather station, mined ore samples, experimented
with plants, and studied ocean floor geology. They also
experimented with a trained porpoise named Tuffy to do courier work
between the habitat and the surface.

Construction
of SEALAB IIís cylinder endbell used technology ahead of its
time. The large dish-shaped cap was formed from a sheet of
one-inch thick flat steel placed over a die. One hundred pounds
of C-4 plastic explosive were distributed on the side of the blank
opposite the die. The whole packageódie, blank, and charge,
weighing 60 tons totalówas lowered 30 feet beneath the surface of
San Francisco Bay where the explosive was detonated. In
approximately .004 seconds the end bell was formed. Explosive
metal shaping on this scale had never been attempted
before.

The pictures below
are from Walt Mazzone's archives and official US Navy
photographs

SEALAB II
being submerged

Samantha the Sea Lion begs for
her supper after being called to the small boat by Mike
Greenwood, psychologist with SEALAB II. 1 Oct
1965.

Dr. Robert Sonnenburg,
(left) talks over the coming day's schedule with Team
Leader Chief Torpedoman Robert Sheats.5 Oct
1965.